f/1776 add error handling

src/index.test.ts

@@ -154,6 +154,85 @@ describe('Output Plugin', () => {
     // TODO test stream error
   });
 
+  it('returns 400 when searchRequest returns 400', async () => {
+    [ plugin, app ] = buildPluginAndApp();
+
+    plugin.model = {
+      pullStream: jest.fn().mockRejectedValue({ status: 400, message: 'A validation error' })
+    }
+
+    await request(app)
+      .get('/dcat')
+      .set('host', siteHostName)
+      .expect('Content-Type', /application\/json/)
+      .expect(400)
+      .expect(res => {
+        expect(plugin.model.pullStream).toHaveBeenCalledTimes(1);
+        expect(res.body).toBeDefined();
+        expect(res.body.error).toEqual('A validation error');
+      });
+  });
+
+  it('returns 404 when provided domain does not exist and domain service returns appropriate message', async () => {
+    [ plugin, app ] = buildPluginAndApp();
+
+    mockFetchSite.mockRejectedValue({ message: 'DOMAIN DOES NOT EXIST :: 404' })
+    await request(app)
+      .get('/dcat')
+      .set('host', siteHostName)
+      .expect('Content-Type', /application\/json/)
+      .expect(404)
+      .expect(res => {
+        expect(res.body).toBeDefined();
+        expect(res.body.error).toEqual('DOMAIN DOES NOT EXIST :: 404');
+      });
+  });
+
+  it('returns 500 when provided domain does not exist and domain service returns wrong message', async () => {
+    [ plugin, app ] = buildPluginAndApp();
+
+    mockFetchSite.mockRejectedValue({ message: 'DOMAIN DOES NOT EXIST :: 403' })
+    await request(app)
+      .get('/dcat')
+      .set('host', siteHostName)
+      .expect('Content-Type', /application\/json/)
+      .expect(500)
+      .expect(res => {
+        expect(res.body).toBeDefined();
+        expect(res.body.error).toEqual('DOMAIN DOES NOT EXIST :: 403');
+      });
+  });
+
+  it('returns 404 when provided domain represents a private site', async () => {
+    [ plugin, app ] = buildPluginAndApp();
+
+    mockFetchSite.mockRejectedValue({ message: 'PRIVATE SITE', response: { error: { code: 403 } } })
+    await request(app)
+      .get('/dcat')
+      .set('host', siteHostName)
+      .expect('Content-Type', /application\/json/)
+      .expect(404)
+      .expect(res => {
+        expect(res.body).toBeDefined();
+        expect(res.body.error).toEqual('PRIVATE SITE');
+      });
+  });
+
+  it('returns 500 when ArcGIS returns wrong error for a site item', async () => {
+    [ plugin, app ] = buildPluginAndApp();
+
+    mockFetchSite.mockRejectedValue({ message: 'PRIVATE SITE' })
+    await request(app)
+      .get('/dcat')
+      .set('host', siteHostName)
+      .expect('Content-Type', /application\/json/)
+      .expect(500)
+      .expect(res => {
+        expect(res.body).toBeDefined();
+        expect(res.body.error).toEqual('PRIVATE SITE');
+      });
+  });
+
   describe('configuration via query params', () => {
     let mockGetDataStreamDcatUs11;
 

src/index.ts

@@ -4,7 +4,7 @@ import * as _ from 'lodash';
 
 import { version } from '../package.json';
 import { getDataStreamDcatUs11 } from './dcat-us';
-import { fetchSite, getHubApiUrl, getPortalApiUrl, IHubRequestOptions } from '@esri/hub-common';
+import { fetchSite, getHubApiUrl, getPortalApiUrl, IHubRequestOptions, RemoteServerError } from '@esri/hub-common';
 import { IContentSearchRequest } from '@esri/hub-search';
 
 const portalUrl = config.has('arcgisPortal')
@@ -34,7 +34,7 @@ export = class OutputDcatUs11 {
 
     try {
       const hostname = req.hostname;
-      const siteModel = await fetchSite(hostname, this.getRequestOptions(portalUrl));
+      const siteModel = await this.fetchSite(hostname, this.getRequestOptions(portalUrl));
 
       // Use dcatConfig query param if provided, else default to site's config
       let dcatConfig = typeof req.query.dcatConfig === 'string'
@@ -53,7 +53,7 @@ export = class OutputDcatUs11 {
       const id = String(req.query.id || '');
       req.res.locals.searchRequest = this.getDatasetSearchRequest(id, portalUrl, apiTerms) || this.getCatalogSearchRequest(_.get(siteModel, 'data.catalog'), portalUrl, apiTerms);
 
-      const datasetStream = await this.model.pullStream(req);
+      const datasetStream = await this.getDatasetStream(req);
 
       datasetStream
         .pipe(dcatStream)
@@ -62,7 +62,20 @@ export = class OutputDcatUs11 {
           res.status(500).send(this.getErrorResponse(err));
         });
     } catch (err) {
-      res.status(500).send(this.getErrorResponse(err));
+      res.status(err.status || 500).send(this.getErrorResponse(err));
+    }
+  }
+
+  private async fetchSite(hostname: string, opts: IHubRequestOptions) {
+    try {
+      return await fetchSite(hostname, opts);
+    } catch (err) {
+
+      // Throw 404 if domain does not exist (first) or site is private (second)
+      if (err.message.includes(':: 404') || err.response?.error?.code === 403) {
+        throw new RemoteServerError(err.message, null, 404);
+      }
+      throw new RemoteServerError(err.message, null, 500);
     }
   }
 
@@ -119,6 +132,17 @@ export = class OutputDcatUs11 {
     };
   }
 
+  private async getDatasetStream(req: Request) {
+    try {
+      return await this.model.pullStream(req);
+    } catch (err) {
+      if (err.status === 400) {
+        throw new RemoteServerError(err.message, null, 400);
+      }
+      throw new RemoteServerError(err.message, null, 500);
+    }
+  }
+
   private getErrorResponse(err: any) {
     return {
       error: _.get(